best way to play iTunes music through xbox extender for free?

I just got an xbox for Christmas, I am trying to figure everything out with it still, so please bear with me. I am trying to find the best way to play my itunes library through my xbox. When I did a search on google, all I was able to find was mce tunes (which only has a free trial) and hp tunes which comes/came with hp machines. The more control over the library, the better.
Any ideas/pointing me in the right direction would be greatly appreciated.
thanks in advance...

You can try out tversity. That's what I use to stream all my content from my PC to my 360, and I never get lag with it (well when using it with the 360). I've been streaming my Video and Music to it, and haven't had problems with it yet. And it works with other systems too, like the PS3, Wii, and I think the PSP is supported too.

Thank you very much for the reply. So it looks likes tversity works pretty much like windows media center then? That is awesome. I will be installing it tonight. I was looking around and I found a program called musicbridge. I guess it syncs itunes and wmp info... songs ratings and playlists. One of the reviews said that they were able to play itunes on their xbox now. I'll also be giving that a try,

Ok, So I installed tverstity last night and it is awesome. I was able to play all of my songs from iTunes on my xbox. The only thing that wasn't amazing about it was that I was unable to access my playlists or anything like that. I had a thought though. The reason that I use iTunes is that I have an iPod touch that I use all the time. It has a nifty little program called remote that allows me to control iTunes on my computer using my iPod. What my new question is, is there a way to just stream what iTunes is playing to the xbox... while still having the computer have control? More or less use my xbox with something along the lines of airtunes? any help/ideas would be greatly appreciated. thanks,